Combat Mass is that portion of an object's mass that, in Starship-to-starship or starship-to-planet combat, contributes to defense and resists damage. The Combat Mass of the various combat objects will be defined here.
The Combat Mass of a planet is equal to 100 KT plus the number of defense posts on the planet, added to the Combat Mass of any starbase in orbit of the planet. A planet without defense posts will not have shields.
The Combat Mass of a starbase is equal to the number of defense posts on the starbase. If the starbase is inside of the radiation halo of a star cluster, and was built by a race other than the Robots, the Combat Mass is increased by 200 KT, due to the additional shielding in these starbases.
It should be noted that a starbase will never fight by itself. It will always fight with the planet it orbits, and its Combat Mass is added to the Combat Mass of that planet. If the planet has no defense posts, the starbase will refuse to fight.
The Combat Mass of a starship is equal to its hull mass, plus bonuses.
It should be noted that Combat Mass bonuses do not increase the PBP/PP that are generated when an enemy starship is destroyed.
Destruction of short-range fighters does not generate any PBP/PP.